SEMICONDUCTOR DEVICE HAVING BURIED WORDLINES

摘要

A memory device includes a substrate having thereon a plurality of active areas that are isolated from one another by a shallow trench isolation (STI) region. A plurality of digitlines is arranged along a first direction on the substrate. A plurality of buried wordlines is arranged in wordline trenches in the substrate along a second direction that is orthogonal to the first direction. A plurality of thicker portions and thinner portions are alternately and repeatedly arranged in each of the wordline trenches to thereby constitute each of the buried wordlines. Each of the thinner portions is arranged between two ends of adjacent two of the active areas.

主权项

1. A memory device, comprising:
a substrate having thereon a plurality of active areas that are isolated from one another by a shallow trench isolation (STI) region; a plurality of digitlines arranged along a first direction on the substrate; and a plurality of buried wordlines arranged in wordline trenches in the substrate along a second direction that is orthogonal to the first direction, wherein the wordline trenches have the same trench depth below a main surface of the substrate, wherein each of the buried wordlines comprises a plurality of top surfaces, and wherein said top surfaces of each of the buried wordlines are alternately and repeatedly in a higher horizontal level and a lower horizontal level along the second direction.